Getting Started

Overview

Using the IncrementalLoadingCollection<T> is easy. You can use it in place of an ObservableCollection<T> as an ItemsSource for a ListView or GridView control in any Windows Universal app.

To use the IncrementalLoadingCollection<T> you must provide the class with a data source that is capable of loading data sequentially by implementing the IVirtualisedDataSource<T>.

1. Create a new page
2. Add a ListView or GridView control to the page
3. Create a virtualised data source that implements IVirtualisedDataSource<T>
4. Create an instance of the IncrementalLoadingCollection<T> using your data source
5. Bind the ItemsSource property of the ListView or GridView to the collection

Walkthrough

1. Select File|New|Project... in Visual Studio 2013
2. Select Blank App (Windows) from Templates|Visual C#|Store Apps
3. Name the project then click OK
4. Right click over the Project in Solution Explorer and select Manage NuGet Packages...
5. With Online|nuget.org selected, search for IncrementalLoadingCollection
6. Select Install to install the package
7. Open MainPage.xaml
8. Add the following code inside the default Grid

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<ListView x:Name="ListView" />

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9. Right click over the Project in Solution Explorer and select Add|Class
10. Name the class GeneratingDataSource.cs
11. Add the following code into the file:

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public class GeneratingDataSource : IVirtualisedDataSource<int>
{
    private readonly int _count;

    public GeneratingDataSource(int count = 1000000)
    {
        _count = count;
    }

    public Task<int> GetCountAsync()
    {
        return Task.FromResult(_count);
    }

    public Task<IEnumerable<int>> GetItemsAsync(uint startIndex, uint count)
    {
        return Task.FromResult(Enumerable.Range((int)startIndex, (int)count));
    }
}

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12. Open MainPage.xaml.cs
13. Add the following code after the this.Initialize();

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var dataSource = new GeneratingDataSource();
var collection = new IncrementalLoadingCollection<int>(dataSource);
ListView.ItemsSource = collection;

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Note that the IncrementalLoadingCollection is implemented as a Portable Class Library for Universal apps, so you can use it in apps targeting Windows, Windows Phone, or Universal apps.